DESIGN OF AN AIRBORNE OPTIC FIBER DATA BUS SYSTEM

The development,application,communication protocol and system structure of an airborne data bus system are discussed in this paper with emphasis on the design of hardware, software and optical fiber transmission system of the bus controller and remote terminal. Some experiments and their results are also given in this paper.

A high-fidelity memory scheme for quantum data buses

A novel quantum memory scheme is proposed for quantum data buses in scalable quantum computers by using adjustable interaction. Our investigation focuses on a hybrid quantum system including coupled flux qubits and a nitrogen–vacancy center ensemble. In our scheme, the transmission and storage（retrieval） of quantum state are performed in two separated steps, which can be controlled by adjusting the coupling strength between the computing unit and the quantum memory. The scheme can be used not only to reduce the time of quantum state transmission, but also to increase the robustness of the system with respect to detuning caused by magnetic noises. In comparison with the previous memory scheme, about 80% of the transmission time is saved. Moreover, it is exemplified that in our scheme the fidelity could achieve 0.99 even when there exists detuning, while the one in the previous scheme is 0.75.

Route Temporal⁃Spatial Information Based Residual Neural Networks for Bus Arrival Time Prediction

Bus arrival time prediction contributes to the quality improvement of public transport services.Passengers can arrange departure time effectively if they know the accurate bus arrival time in advance.We proposed a machine⁃learning approach,RTSI⁃ResNet,to forecast the bus arrival time at target stations.The residual neural network framework was employed to model the bus route temporal⁃spatial information.It was found that the bus travel time on a segment between two stations not only had correlation with the preceding buses,but also had common change trends with nearby downstream/upstream segments.Two features about bus travel time and headway were extracted from bus route including target section in both forward and reverse directions to constitute the route temporal⁃spatial information,which reflects the road traffic conditions comprehensively.Experiments on the bus trajectory data of route No.10 in Shenzhen public transport system demonstrated that the proposed RTSI⁃ResNet outperformed other well⁃known methods(e.g.,RNN/LSTM,SVM).Specifically,the advantage was more significant when the distance between bus and the target station was farther.

POTENTIAL: A Highly Adaptive Core of Parallel Database System

POTENTIAL is a virtual database machine based on general computing platforms, especially parallel computing platforms. It provides a complete solution to high-performance database systems by a 'virtual processor + virtual data bus + virtual memory' architecture. Virtual processors manage all CPU resources in the system, on which various operations are running. Virtual data bus is responsible for the management of data transmission between associated operations, which forms the hinges of the entire system. Virtual memory provides efficient data storage and buffering mechanisms that conform to data reference behaviors in database systems. The architecture of POTENTIAL is very clear and has many good features, including high efficiency, high scalability, high extensibility, high portability, etc.

Bus Scheduling Using a Skip-Stop Strategy Based on Stop Relevance

This research aims to propose an efficient and economic operation mode for bus scheduling optimization by combining with the skip-stop buses and all-stop buses.The skip-stop tactics in bus operation provide service of high efficiency,good punctuality and high speed for long distance commuters,which attracts wide scholarly attention.This paper establishes a model to quantitatively evaluate the relevance between stops,and then develops a new optimization method of skip-stop tactics using the data sets of IC card and bus GPS trajectory.A collaborating scheduling optimization model considering the support and confidence among the stops is proposed to precisely suit passengers’demands and improve bus service.The optimization objective is to reduce the passengers’total travel time,the number of vehicles in use,and operation energy for both the user’s and the operator’s benefits.This methodology is developed for a single-directional route using a multi-decision choice model with genetic algorithm applied to attain efficient solutions.A case study of Qingdao,which is assessed in this new model,shows a reduction of 18.31%in total passenger travel time and 17.65%in the operational inputs as compared with solutions that do not consider the skip-stop tactics.